Get both fries and onion rings at Burger King.

Get a grilled cheese sandwich at McDonald's.

Grilled cheese sandwiches are a great option for light appetites or vegetarians. Simply order a grilled cheese, specifying that you'd like the bun grilled for maximum toasty flavor. This item costs around $1.

Get a root beer float at Chick-fil-A.

Get a double grilled cheese burger at Five Guys.

If you want a really decadent burger, you can ask Five Guys to make your burger between two grilled cheese sandwiches.

Get your favorite dipping sauce at McDonald's.

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McDonald's has more dipping sauces than anyone realizes, according to #hackthemenu. In addition to the traditional BBQ sauce, you can order Sweet and Sour, Honey Mustard, Chipotle BBQ, Tangy BBQ, Spicy Buffalo, Sweet Chili, Hot Mustard, and Creamy Ranch.

Get a cheaper "Big Mac" at McDonald's.

Big Macs typically cost around $4. If this price is steep for you but you love the flavor, it's easy to get something similar for $1.49 or so. Just order a McDouble without ketchup, then add lettuce and Big Mac sauce. You'll have all the taste of a Big Mac.